CRI-HOM: A novel chemical mechanism for simulating highly oxygenated organic molecules (HOMs) in global chemistry–aerosol–climate models

Atmospheric chemistry and physics, Journal Year: 2020, Volume and Issue: 20(18), P. 10889 - 10910

Published: Sept. 22, 2020

Abstract. We present here results from a new mechanism, CRI-HOM, which we have developed to simulate the formation of highly oxygenated organic molecules (HOMs) gas-phase oxidation α-pinene, one most widely emitted biogenic volatile compounds (BVOCs) by mass. This concise scheme adds 12 species and 66 reactions Common Representative Intermediates (CRI) mechanism v2.2 Reduction 5 enables representation semi-explicit HOM treatment suitable for long-term global chemistry–aerosol–climate modelling, within comprehensive tropospheric chemical mechanism. The key features are (i) autoxidation peroxy radicals hydroxyl radical ozone initiated (ii) multiple generations radicals, (iii) accretion products (dimers), (iv) isoprene-driven suppression product formation, as observed in experiments. has been constructed through optimisation against series flow tube laboratory predicts yield 2 %–4.5 % under conditions low moderate NOx, line with experimental observations, reproduces qualitatively decline concentration at higher NOx levels. gives that also increases temperature, our compares favourably some limited observations [HOM] boreal forest Finland southeast USA. reproduction HOMs is step forward it climate models capture interaction between major BVOC species, along potential climatic feedbacks. demonstrated when used atmospheric profiles over rainforest; different isoprene concentrations result distributions, illustrating importance interactions composition climate. Finally particle nucleation rates calculated present-day pre-industrial atmospheres suggest “sulfuric-acid-free” can compete effectively other pathways forest, particularly period, important implications aerosol budget radiative forcing.

Language: Английский

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Terpene emissions from boreal wetlands can initiate stronger atmospheric new particle formation than boreal forests

Communications Earth & Environment, Journal Year: 2022, Volume and Issue: 3(1)

Published: April 19, 2022

Abstract Aerosols and their interaction with clouds constitute the largest uncertainty in estimating radiative forcing affecting climate system. Secondary aerosol formation is responsible for a large fraction of cloud condensation nuclei global atmosphere. Wetlands are important to budgets methane carbon dioxide, but potential role wetlands has not been investigated. Here we use direct atmospheric sampling at Siikaneva wetland Finland investigate emission volatile organic compounds, subsequently formed clusters aerosols. We find that terpenes initiate stronger new particle than typically observed over boreal forests that, addition emissions which cause warming effect, also have cooling effect through these terpenes. suggest produced by melting permafrost need be taken into consideration as sources secondary particles when increasing extent future change.

Language: Английский

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Advancing Cross‐Disciplinary Understanding of Land‐Atmosphere Interactions

Journal of Geophysical Research Biogeosciences, Journal Year: 2022, Volume and Issue: 127(2)

Published: Jan. 12, 2022

Abstract The evolution of disciplinary silos and increasingly narrow boundaries have together resulted in one‐sided approaches to the study land‐atmosphere interactions—a field that requires a bi‐directional approach understand complex feedbacks interactions occur. integration surface flux atmospheric boundary layer measurements is therefore essential advancing our understanding. Land‐Atmosphere 2021 workshop (held virtually, June 10‐11, 2021) involved almost 300 participants from around world promoted cross‐discipline collaboration by way talks invited speakers, moderated discussions, breakout sessions, virtual poster session. focused on five main theme areas: “big picture” overview, instrumentation remote sensing, modeling, water, aerosols clouds. In groups, there were frequent calls for more AmeriFlux sites be instrumented height measurements, development some “super sites” where profiling instruments would deployed. There was further agreement need standardization various datasets. also consensus funding agencies willing support sorts large projects (including associated instrumentation) which can drive interdisciplinary work. Early‐career scientists, particular, expressed enthusiasm working across but noted financial training opportunities so they better prepared Investment these career enable today's cohort early‐career scientists advance frontiers work over next couple decades.

Language: Английский

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Emissions of biogenic volatile organic compounds from adjacent boreal fen and bog as impacted by vegetation composition

The Science of The Total Environment, Journal Year: 2022, Volume and Issue: 858, P. 159809 - 159809

Published: Nov. 3, 2022

Peatland ecosystems emit biogenic volatile organic compounds (BVOC), which have a net cooling impact on the climate. However, quality and quantity of BVOC emissions, how they are regulated by vegetation peatland type remain poorly understood. Here we measured emissions with dynamic enclosures from two major boreal types, minerotrophic fen an ombrotrophic bog situated in Siikaneva, southern Finland experimentally assessed role removing vascular or without moss layer. Our measurements four campaigns during growing seasons 2017 2018 identified 59 nine different chemical groups. Isoprene accounted for 81 % emissions. Measurements also revealed uptake dichloromethane. Total isoprene, monoterpenoids, sesquiterpenes, homoterpenes, green leaf volatiles were tightly connected to plants. sesquiterpene associated sedges, whereas monoterpenoids homoterpenes shrubs. Additionally, isoprene alkane higher than significantly contributed intact fen. During extreme drought event 2018, halides absent. results indicate that climate change increase shrub cover increased frequency weather events may negative total otherwise predicted warmer temperatures. these changes accompanied emission quality. As differ their capacity form secondary aerosols, ultimate be altered.

Language: Английский

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Quantifying the impacts of environmental stress factors on biogenic volatile organic compound emissions in China

Agricultural and Forest Meteorology, Journal Year: 2025, Volume and Issue: 366, P. 110480 - 110480

Published: March 9, 2025

Language: Английский

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